Table 4.

Villus height, crypt depth, and thickness of muscularis mucosae (micrometer) of broilers supplemented with either an antibiotic or a phytogenic feed additive during 1–39 days of age*.

	Dietary treatments†			SEM	P value
	Control	AGP	PFA
Duodenum
Villus height	2549.1b	3481.1a	2903.4bab	140.23	0.02
Crypt depth	45.3	42.7	32.8	2.55	0.10
Mucosa thickness	387.1a	183.9b	230.4b	22.69	<0.01
Jejunum
Villus height	2583.6c	2969.9b	3290.1a	280.51	<0.01
Crypt depth	29.8a	31.1a	20.2b	1.31	<0.01
Mucosa thickness	206.8	215.6	212.9	6.85	0.88
Ileum
Villus height	2050.1b	2736.4a	2839.9a	94.03	<0.01
Crypt depth	34.1	30.9	31.6	1.04	0.45
Mucosa thickness	320.3a	233.9b	211.8b	14.31	<0.01

Means with dissimilar letters in a row varied significantly.

*Means of 12 birds per treatment. Birds were randomly selected and euthanized at 39 days of age.

^†Supplemented with either an antibiotic growth promoter, bacitracin methylene disalicylate, 500 mg/kg (AGP), or a phytogenic feed additive (Digestarom^® Poultry) 150 mg/kg (PFA). The control group received the unsupplemented basal diet.